The present invention relates to an arrangement for processing signals which are grouped in periodic clusters, such as images, and intended to be transmitted and/or stored block-wise over/on a passband-limited information carrier, which implies a reduction in the quantity of information components to be transmitted and/or stored.
The invention also relates to a signal transmission and/or storage system comprising a transmission stage and, after transmission and/or storage of the signals transmitted via a passband-limited information carrier which implies a reduction processing of the quantity of information components to be transmitted and/or stored, a receiving and/or read stage of the transmitted and/or stored signals, and in which the said transmission stage incorporates such a processing arrangement.
The invention also relates to a processing arrangement for signals which were previously transmitted and/or stored after reduction of the quantity of information components to be transmitted and/or stored, which is effected in accordance with a first mode of transmission and/or storage referred to as compensated mode using a temporal sub-sampling sub-assembly having a predetermined sub-sampling ratio and being provided to supply a first signal sequence, or in accordance with a second mode of transmission and/or storage referred to as fall-back mode using a fall-back processing sub-assembly provided to add to the said first sequence a second signal sequence, the choice of the said modes being effected with the aid of a decision-taking sub-assembly and on the basis of motion information components, which are also transmitted and/or stored, and an information component comparison associated with either one or the other mode, respectively.
The invention further relates to an arrangement for processing signals which were previously transmitted and/or stored after a reduction of the quantity of information components to be transmitted and/or stored, effected in accordance with a first mode of transmission and/or storage, referred to as compensated mode and in which mode with the aid of a temporal sub-sampling sub-assembly having a predetermined sub-sampling ratio and being intended to supply a first signal sequence, or in accordance with a second mode of transmission and/or referred to as storage fall-back mode and in which mode with the aid of a fall-back processing sub-assembly intended to add to the said first sequence a second sequence of signals, with a spatial sub-sampling of the said sequences, and for effecting the alternate selection of one or the other of the spatially sub-sampled sequences, the choice of the said mode being effected with the aid of a decision-taking sub-assembly and on the basis of motion information components which are also transmitted and/or stored, and a comparison of the information components which are associated with either one or the other mode, respectively, with a view to selecting either the output of the said motion compensation sub-assembly or the output of the said fall-back processing sub-assembly.
Finally, the invention also relates to a signal transmission and/or storage system comprising a transmission stage and after transmission and/or storage of the signals transmitted via a passband-limited information carrier which implies a reduction processing of the quantity of information components to be transmitted and/or to be stored, a receiving and/or read stage for the transmitted and/or stored signals.
This invention has a particularly interesting application in the case in which the signals to be processed include information components which represent animated images and in which a compact disc is used as the carrier of the transmitted and/or stored signals.
The transmission and/or storage of a very large quantity of information components, associated, for example, with images, generally implies a compression of the signals to be transmitted and/or to be stored, that is to say a reduction, in a predetermined ratio, of their number. The reduction ratio is inter alia determined by the fact that a sufficient quantity of signals must be preserved to avoid that the overall information they carry is not degraded too much, for example by the fact that one must preserve an acceptable picture quality within the scope of the cited Application.
The majority of the presently known signal coding methods to realize this flow rate reduction are based on orthogonal transforms of the discrete cosine transform type, which allow a flow-rate reduction in a ratio of the order of 10 to 1. For a significant number of applications and, for example when used in storing or processing images on compact disc, this ratio is not sufficient and a complementary reduction processing in a ratio of 2 to 1 was found to be indispensable.